LIQUI MOLY TOPTEC 4100 0W40 vs REDLINE 10W40

[g60]

Since I have to travel for 50 km in order to buy my motor oil, decided to check a local store. Their proposal was the LIQUI MOLY TOPTEC 4100 0W40. (VW g60, unmodified but chipped engine). Although I am a REDLINE customer for years, and because of the moderate difficulty to buy it, decided to give the LIQUI MOLY a try, changing and the oil filter, (MANN). Immediately my impression was that the oil and the cooling liquid temperatures went up, as well as, the engine noise became rough. For this reason, finally, bought three quarts of REDLINE 10W40, (the recommended oil by their oil finder), to change again the oil, mixing it with the fresh LIQUI MOLLY, (~ 1 l of it remaining into the engine). But before the changing had the idea to check, under the same conditions, the engine's noise, using my decibelometer. The measurement after the changing to the REDLINE was a big surprise. The sound level, some seconds after the starting, went down 20-25 db. Here are the relevant measurement videos, cold start, in both cases, at 30°C, (unfortunately the sound was off at the moment of the record):

Do you think that such a tremendous difference is possible between two fresh oils having similar specs?

 

[RooflessVW]

Yea, I'd say it's possible. My G60 was happiest on GTX 10W-40. Have you rebuilt the G-Lader yet?

 

[g60]

The g-lader is a new one, changed at ~ 250.000 km.. The car now has ~ 296.000 km.. (No engine repairs).

 

[Audios]

Any chance the secondary air pump was on in the first vid? 25 db is a lot of change from just oil.

 

[Trav]

That's exactly what I was thinking. Good catch.

 

[g60]

Originally Posted By: Audios

Any chance the secondary air pump was on in the first vid? 25 db is a lot of change from just oil.

There is no secondary pump to this car but may be the clima's/radiator's, auto start, when cranking, fan. I 'll check it in some hours and I 'll report. Thank you very much for the good idea.

 

[g60]

Strangely enough I got the same results even if the, underneath the decibelometer, fan is on or off. Here is the video, (hopefully with sound this time). The video gives firstly the measurement having the fan in the off position, and continues with the fan on.

The good thing is that, such an experiment, could very easily being replicated, by anyone interested, with these or with any other oil. Can you find what else may be wrong please?

 

[g60]

I will post two more measurements: #1 With engine at the normal operation temperature. #2 Some thousand kilometers after, at cold and at normal temperature. The Syncro Heresy

 

[g60]

Correction: 30 C° instead 30° C. Thank you.

 

[g60]

With the engine at the normal operation temperature:

This is the one of the two promised video. The second, (& 3rd), one is due some thousand kilometers after. The oil is the REDLINE 10W40, and the noise is even more reduced when warm.

 

[aquariuscsm]

I always love posts like this,always very interesting. Very first of the day startups is always what intrigues me. You should repeat the video process with your camera and sound device under the hood while you start the cold engine vs while already having it running.

 

[g60]

Originally Posted By: aquariuscsm

I always love posts like this,always very interesting. Very first of the day startups is always what intrigues me. You should repeat the video process with your camera and sound device under the hood while you start the cold engine vs while already having it running.

Nice idea. Thank you. We 'll see.